“[Diet Coke is] the most annoying beverage a flight attendant can pour for a passenger in flight, because in the time it takes us to fill one cup, we could have served an entire row of passengers,” wrote flight attendant Heather Poole, who revealed all in her book.

Even on the ground, Diet Coke foams up more than non-diet beverages — but at a cruising altitude? Even more so. According to the Huffington Post, it’s the lack of sugar in Diet Coke that makes the carbonation last longer — and pouring it over a cup of ice only exacerbates the problem.

“Generally, when sparkling beverages are poured at room temperature from a can and over ice, the fizz is increased,” a Coke representative told the publication.

Poole has even had nightmares about serving a cup of never-ending Diet Coke to a passenger before the plane lands.

And though flight attendants won’t “hate you”, per se, if you ask for the drink, it can slow down the in-flight service immensely. Still, some flight attendants have learned to combat the foaming issue with one simple trick, as seen below: